Impulse burner system and burner therefor

ABSTRACT

A burner system comprising a rotary shaft having an eccentric thereon, means for rotating the shaft, a pump rod connected to the eccentric for delivering a pulsating flow of a fuel to a burner where it is mixed with air, electrical ignition means driven by the shaft, a spark gap means associated with the burner for igniting the gaseous mixture, and the burner structure used in the system.

United States Patet 1 Williams 51 June 5, 1973 [54] IMPULSE BURNER SYSTEM AND BURNER THEREFOR [75] Inventor: Steele D. Williams, Chattanooga,

Tenn,

[73] Assignees: F. Edward Harrington, Willowdale, Ontario, Canada; Lloyd F. Anderson, Deerfield, Wis.

[22] Filed: Mar. 1, 1972 [21] Appl. No.: 230,909

[52] U.S. Cl. ..431/158, 431/266, 431/353 [51] Int. Cl. ..F23r 1/06 [58] Field of Search ..431/1, 158, 266, 431/353, 173; 60/3976 [56] References Cited UNITED STATES PATENTS 1,137,328 4/1915 Jennings ..431/1 X 1,394,576 10/1921 Parrish ..431/1 3,606,867 9/1971 Briffa ..431/1 X 1,671,352 5/1928 DeGuise ..431/173 X Primary ExaminerEdward G. Favors Attorney- B. Edward Shlesinger, J r., George A. Arkwright, Harold H. Dutton,.lr. et al.

[57] ABSTRACT A burner system comprising a rotary shaft having an eccentric thereon, means for rotating the shaft, a pump rod connected to the eccentric for delivering a pulsating flow of a fuel to a burner where it is mixed with air, electrical ignition means driven by the shaft, a spark gap means associated with the burner for igniting the gaseous mixture, and the burner structure used in the system.

12 Claims, 4 Drawing Figures PATENIEUJ'JH 5191a SHEET 2 UF 3 PATENT {51:24 51915 SHEET 3 OF 3 IMPULSE BURNER SYSTEM AND BURNER THEREFOR This invention relates to a burner system capable of producing temperatures on the order of 6000F and a burner for use with the system.

The prior art is replete with many burners and burner systems for various uses, ranging from relatively low temperature uses on the order of 5001000F, up to 30004000F. However, relatively few burners are capable of temperatures greater than 4000F because of various limiting factors such as the fuel utilized, the ignition system, the combustion chamber design, and the like.

However, high temperature burners which are capable of producing temperatures in excess of 4000F and even preferably in excess of 6000F, are very desirable from a commercial standpoint. This is particularly true in the metallurgical industry where high temperatures are needed for the pyrometallurgical refining of various metals such as titanium, and the like.

One disadvantage of prior art burners which have been capable of high temperature operation has been that their use at high temperatures has been possible for only short periods of time to prevent burning up or melting of the burner. Accordingly, it is a primary object of this invention to provide a burner system capable of operation at temperatures on the order of 6000F.

Another object of this invention is to provide a burner capable of sustained operation at temperatures on the order of 6000F.

A further object of this invention is to provide a compact yet highly efficient burner structure.

Still another object of this invention is to provide a burner structure which may be cooled during its operation and still maintain a high thermal output.

Still a further object of this invention is to provide a burner system whereby a plurality of burners may be operated from a central station.

Yet a further object of this invention is to provide a burner system which utilizes pulsed fuel flow.

Yet another object of this invention is to provide a burner system which utilizes magneto-fired sparkedgap ignition.

These and other objects and advantages of this invention will become apparent when considered in light of the following description and claims when taken together with the drawings in which:

FIG. I is a schematic illustration showing the burner system of this invention;

FIG. 2 is a longitudinal cross-sectional view of one of the burners utilized in FIG. 1;

FIG. 3 is an enlarged sectional view along lines 33 of FIG. 1 and viewed in the direction of the arrows; and

FIG. 4 is a side elevational view of the pump structure shown in FIG. 3.

Referring now to FIG. 1 of the drawings, the overall system generally designated is provided with a suitable support structure 12 on which may be mounted a motor 14. Motor 14 is preferably an electric motor by which suitable connection to electric power may be made through leads 16, or if desired, a hydraulic or other motor may be utilized.

Motor 14 is provided with a pulley 18 on its output shaft 20. A shaft 22 is mounted in suitable bearing blocks 24, and mounted on shaft 22 is a pulley 26. Pulleys 18 and 26 are connected by a suitable drive belt 28 to thus impart rotation to shaft 22. Also mounted on shaft 22 through a suitable clutching arrangement 30 is a magneto 32 of suitable construction. The electrical output of magneto 32 is delivered to a suitable control mechanism or distributor 34.

From the distributor or control mechanism 34, the ignition current is supplied through electrical leads 36 to the burners 38. Burners 38 are connected in any suitable manner to ground as generally designated 40.

Also connected to shaft 22 are a plurality of piston rods 42. Piston rods 42 are connected through eccentrics 44 to the shaft 22 in such a manner that rotation of shaft 22 results in reciprocation of piston rods 42. Piston rods 42 are connected to pistons 46 in pumps 48 as best seen in FIG. 4.

Pumps 48 are in communication with a suitable source of fuel through lines 50. The output of the pumps 48 is delivered to the burners 38 through suitable connections 52.

Referring now to FIGS. 3 and 4, the pumps 48 are seen to include a housing 54 provided with a bore 56 in which the piston 46 travels. The housing 54 may be attached to a suitable support 12 by means of screws 58.

Preferably, the piston rods 42 are provided with a pivotal connection as indicated at 60 to accommodate pendulous movement of the rod 42 during the rotation of the eccentric 44.

Preferably, line 50 is provided with a check valve 62, and line 52 is provided with a check valve 64. Check valves 62 and 64 prevent reverse flow of gases in the corresponding lines 50 and 52.

Preferably, the fuel which is utilized in the burner and system of this invention is a gaseous fuel such as natural gas, propane, butane or the like. Such gases have a high heat output and are readily available at minimal expense.

Each of the fuel lines 52 is provided with a Y- connection 66 and line 68 permits the introduction of air from a suitable blower (not shown) or the like. The blower may be driven by the motor 14, either directly or from the shaft 22.

Referring now to FIG. 2, the burner 38 is seen to include a housing 70 of substantially annular configuration. A cover plate 72 is secured to the housing 70 by means of screws 74. An inner annular wall is provided by means of a ring 76 which is secured to cover plate 72 by means of screws 78 and to housing 70 by means of screws 80. An annular member 82 is secured to cover plate 72 by means of bolts 84. Annular member 82 defines a toroidal mixer chamber 86 which is open at its lower end so as to communicate with burner chamber 88 defined by the ring 76. The air fuel mixture passes through line 68 into the mixer chamber 86 tangentially, to thereby provide good mixing of the air and fuel. The inner wall 90 of the mixer chamber 86 serves to position a tubular insulating member 92 therein. An insulating washer 94 is also provided. A conducting electrode core member 96 is provided and held in place by means of a suitable nut 98. In this manner, the electrode core member 96 is insulated from the remainder of the housing which is grounded in a manner shown in FIG. 1. The electrical leads 36 are connected to the electrode core member 96 by a suitable connection.

The electrode core member 96 and the tubular insulating member 92 are drilled in such a manner as to receive the two pairs of perpendicular electrode pins 100 preferably, each pair of the electrode pins 100 comprises two pins which are perpendicular to each other as shown in the drawings.

Positioned within the ring 76 in a pair of grooves 102 are a pair of ring-type electrodes 104. Electrodes 104 are thusly spaced from pin electrodes 100 to provide a spark gap therebetween.

A mounting ring 106 is secured to the lower end of housing 70 by means of a screws 108, and mounting ring 106 thus secures in place the burner cone 1 10. Additionally, screws 112 pass through mounting ring 106 to secure the entire burner 38 to a furnace wall 114.

Housing 70 is provided with a plurality of openings 116 which communicate with a coolant chamber 118 which surrounds the burner chamber 88. Coolant is allowed to flow from a suitable source (not shown) through the openings 116 and circulate in the coolant chamber 1 18.

The tubular insulating member 92 is preferably made of a high temperature material which is an electrical insulator. A suitable material would be any of the variety of ceramics capable of withstanding temperatures in excess of 6000F. Additionally, the burner cone 110 should also be made of a material capable of withstanding high temperatures such as the material known as Erfax.

The operation of the burner system of this invention will now be described. A suitable source of a gaseous fuel such as natural gas supplies the fuel under pressure through line 50 to the pump 48. The pump which is driven by means of motor 14 delivers a pulsing flow of gas to the mixer chamber 86 where it is thoroughly mixed with air from the blower (not shown). The mixture upon entering the chamber 86 swirls therearound and is completely mixed when it enters burner chamber 88. The magneto 32 delivers a charge of electricity through the distributor 34 and the leads 36, to the electrode core member 96 and the electrode pins 100. A spark gap is created between the electrode pins 100 and the ring electrodes 104 to ignite the air-gas mixture in the burner chamber 88. Complete burning of the gas-air mixture is assured by means of the two spaced pair of electrode pins. The flame front travels through the burner cone 110 into the furnace upon which the burner housing 70 is mounted.

As seen in FIG. 1, one motor, magneto, and controller may be utilized to control a plurality of burners. While four such burners are shown, it is obvious that additional burners could be utilized. Obviously, one, two or any other number of burners may be utilized simultaneously. Other types of ignition systems such as an induction coil type, a capacitor discharge type, or the like with suitable distributors, however, the voltage output of a magneto generally is higher and is the pre ferred type. The ignition should be by an intermittent electrical pulse which in the preferred embodiment would be timed with the pulse of fuel so that ignition occurs as the fuel pulse passes through the spark gap.

It has been found that the pulsing gas flow together with the intermittent ignition thereof is one of the prime features which enables the burner and burner system of this invention to attain and maintain extremely high temperatures. Also, it has been found desirable that the ratio of the length of the mixer chamber to the length of the burner chamber be on the order of l:23 for optimum results.

While this invention has been described, it will be understood that it is capable of further modification, and this application is intended to cover any variations, uses and/or adaptations of the invention following in general, the principle of the invention and including such departures from the present disclosure as come within known or customary practice in the art to which the invention pertains, and as may be applied to the essential features hereinbefore set forth, as fall within the scope of the invention or the limits of the appended claims.

What I claim is:

1. A gas burner assembly comprising;

a. a housing,

b. an annular mixer chamber in said housing,

c. means for introducing an air-fuel mixture into said mixer chamber,

d. an annular ignition chamber in said housing adjacent said mixer chamber for receiving said air-fuel mixture from said mixer chamber,

e. spark-gap ignition means in said ignition chamber,

f. said spark-gap ignition means comprising first electrode means centrally positioned in said ignition chamber,-

g. second electrode means peripherally positioned in said ignition chamber and spaced from said first electrode means,

h. a coolant chamber surrounding said ignition chamber, and

i. said housing including burner nozzle means.

2. A burner assembly as in claim 1 and wherein:

a. said mixer chamber, said ignition chamber, and

said nozzle means are substantially cylindrical.

3. A burner assembly as in claim 2 and wherein:

a. said mixer chamber, said ignition chamber, and

said nozzle means are substantially coaxial.

4. A burner assembly as in claim 3 and wherein:

a. said introducing means feeds said air-fuel mixture substantially tangentially into said mixer chamber.

5. A burner assembly as in claim 4 and wherein:

a. said cylindrical mixer chamber includes closure means at one end thereof and opens into said ignition chamber at the other end thereof,

b. said ignition chamber and said nozzle means being open at each end thereof.

6. A burner assembly as in claim 5 and including:

a. means secured to said closure means and extending through said mixer chamber and said ignition chamber for supporting said first electrode means.

7. A burner assembly as in claim 6 and wherein:

a. said supporting means comprises a cylindrical support tube of electrically insulating material,

b. said first electrode means comprising an electrode core member positioned within said support tube and extending out of said housing and being electrically insulated from said housing,

c. an electrode contact pin extending transversely through said support tube and said electrode core member and being in electrical contact with said member.

8. A burner assembly as in claim 7 and including:

a. a pair of said electrode contact pins,

b. said electrode contact pins being positioned substantially perpendicular to each other and spaced from each other.

9. A burner assembly as in claim 8 and wherein:

= a. said second electrode means includes an electrode l ring'member secured to the inner wall of said igniher.

11. A burner assembly as in claim 10 and wherein:

a. said first ring electrode member is positioned adjacent said mixer chamber, and

b. said second ring electrode member is positioned adjacent said burner nozzle means.

12. A burner assembly as in claim 11 and wherein:

a. the ratio of the length of said ignition chamber to the length of said mixer chamber is within the range of about 2:1 to 3:l. 

1. A gas burner assembly comprising: a. a housing, b. an annular mixer chamber in said housing, c. means for introducing an air-fuel mixture into said mixer chamber, d. an annular ignition chamber in said housing adjacent said mixer chamber for receiving said air-fuel mixture from said mixer chamber, e. spark-gap ignition meanS in said ignition chamber, f. said spark-gap ignition means comprising first electrode means centrally positioned in said ignition chamber, g. second electrode means peripherally positioned in said ignition chamber and spaced from said first electrode means, h. a coolant chamber surrounding said ignition chamber, and i. said housing including burner nozzle means.
 2. A burner assembly as in claim 1 and wherein: a. said mixer chamber, said ignition chamber, and said nozzle means are substantially cylindrical.
 3. A burner assembly as in claim 2 and wherein: a. said mixer chamber, said ignition chamber, and said nozzle means are substantially coaxial.
 4. A burner assembly as in claim 3 and wherein: a. said introducing means feeds said air-fuel mixture substantially tangentially into said mixer chamber.
 5. A burner assembly as in claim 4 and wherein: a. said cylindrical mixer chamber includes closure means at one end thereof and opens into said ignition chamber at the other end thereof, b. said ignition chamber and said nozzle means being open at each end thereof.
 6. A burner assembly as in claim 5 and including: a. means secured to said closure means and extending through said mixer chamber and said ignition chamber for supporting said first electrode means.
 7. A burner assembly as in claim 6 and wherein: a. said supporting means comprises a cylindrical support tube of electrically insulating material, b. said first electrode means comprising an electrode core member positioned within said support tube and extending out of said housing and being electrically insulated from said housing, c. an electrode contact pin extending transversely through said support tube and said electrode core member and being in electrical contact with said member.
 8. A burner assembly as in claim 7 and including: a. a pair of said electrode contact pins, b. said electrode contact pins being positioned substantially perpendicular to each other and spaced from each other.
 9. A burner assembly as in claim 8 and wherein: a. said second electrode means includes an electrode ring member secured to the inner wall of said ignition chamber in electrical contact therewith and spaced radially from said electrode contact pins.
 10. A burner assembly as in claim 9 and including: a. a second pair of said electrode contact pins spaced longitudinally on said electrode core member from said first pair of electrode contact pins, and b. a second electrode ring member secured to the inner wall of said ignition chamber in electrical contact therewith and spaced radially from said second pair of electrode contact pins and spaced longitudinally from said first electrode ring member.
 11. A burner assembly as in claim 10 and wherein: a. said first ring electrode member is positioned adjacent said mixer chamber, and b. said second ring electrode member is positioned adjacent said burner nozzle means.
 12. A burner assembly as in claim 11 and wherein: a. the ratio of the length of said ignition chamber to the length of said mixer chamber is within the range of about 2:1 to 3:1. 